Swedish Power Circle, a hub and platform for the power sector, supported by Mine Storage has initiated a study on long duration pumped storage hydropower in mines in the Swedish energy system. The project has been carried out as a master thesis by the two students Sophie Ågren and Alexandra Sederholm from Uppsala University and the first results were presented on Power Circle’s event on long duration energy storage on May 12 in Stockholm.
The study has been done out of a system perspective creating three weather scenarios based upon historical weather data from the Swedish Transmission Operator Svenska Kraftnät’s scenario up to year 2045.. These scenario’s shows a substantial need for long duration storage in Sweden during periods of deficit both from a power and an energy perspective. The most conservative scenario shows a need of 28 units of 100 MW energy storages with an endurance of approximately 10 hours to balance up the deficit, and the central scenario based upon a fraction of energy shortage periods longer than 8 hours the need for long duration storage rises to more than 170 mine storage plants of 100 MW each.
The results suggest that the need for grid-scale energy storage is immense, which was confirmed by the discussion and workshop session following the presentation. The discussion proposed actions on incentives for power quality, grid stability, simplified permitting processes and regulation to enable energy storage solutions that can support the grid and allow more renewables replacing fossil-fueled power generation.